Abdominal no Contrast and Contrast-Enhanced Multi-Slice CT After Orally Diluted Iodide in Diagnosis of Time Segment for Gastrointestinal Fistula Secondary to Acute Pancreatitis / 中国医学影像学杂志

Purpose To evaluate the diagnostic accuracy of abdominal plain scan and contrast-enhanced multi-slice CT after orally diluted iodide in time segment(Post-ODI ANCCE-MSCT)for gastrointestinal fistula(GIF)secondary to acute pancreatitis(AP).Materials and Methods A total of 108 patients with late AP in the prospective and continuously collected database of Hunan Provincial People's Hospital from January 2017 to December 2022 were retrospectively extracted.Their demographic information and clinical features were recorded and GIF were screened by Post-ODI ANCCE-MSCT.The comprehensive clinical diagnosis results within 5 days thereafter were used as reference standards.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of Post-ODI ANCCE-MSCT for diagnosing GIF secondary to AP were calculated using a four-cell table,and the consistency of the two methods was evaluated by Kappa test and McNemar's test.Results Sensitivity was 91.5%(95%CI 78.7%-97.2%),specificity was 98.4%(95%CI 90.0%-99.9%),positive predictive value was 97.7%(95%CI 86.5%-99.9%),negative predictive value was 93.8%(95%CI 84.0%-98.0%),and the accuracy was 95.4%(95%CI 91.4%-99.3%),respectively.The Kappa value was 0.905,and P value was 0.375 via McNemar's test.Conclusion Post-ODI ANCCE-MSCT can diagnose GIF secondary to AP in a simple,non-invasive,rapid and accurate way,and provide earlier,more accurate and reliable image basis for clinical diagnosis and treatment.

Preoperative prediction for lymph node metastasis of rectal nonmucinous adenocarcinoma based on radiomics classifier / 中南大学学报(医学版)

To determine the value of radiomics in identifying lymph node (LN) metastasis in patients with rectal nonmucinous adenocarcinoma.
 Methods: Imaging data of 91 patients were retrospectively analyzed (61 in the training set and 30 in the test set). A total of 1 301 radiomics features were extracted from high-resolution T2-weighted images of the whole primary tumor. The least absolute shrinkage and selection operator (LASSO) logistic regression was performed to choose the optimal features and construct a radiomics classifier in the training set. Its discrimination performance was compared with that of morphological criteria by receiver operating characteristic (ROC) curve analysis, which was validated in the test set.
 Results: The radiomics classifier combined with five key features was significantly associated with LN metastasis, which distinguished LN metastasis with an area under curve (AUC) at 0.874 (95% CI 0.787 to 0.960) in the training set, and the performance was similar in the test set (AUC 0.878, 95% CI 0.727 to 1.000). The AUCs according to the morphological criteria in the training set and test set were 0.619 (95% CI 0.487 to 0.752) and 0.556 (95% CI 0.355 to 0.756), respectively. Discrimination of the radiomics classifier was superior to that of morphological criteria in both the two datasets (both P <0.05).
 Conclusion: The radiomics classifier provides individualized risk estimation for LN metastasis in rectal nonmucinous adenocarcinoma patients and it has the advantage over the morphological criteria.

CT imaging features and their correlation with pathological findings of solid pseudopapillary tumor of pancreas / 生物医学工程学杂志

To analyze the CT features of solid pseudopapillary tumor of pancreas (SPTP), and correlation with the pathological findings of the disease so as to improve the diagnostic abilities, the CT images and the clinical manifestations, we retrospectively analyzed the pathological materials of 23 cases with surgery and pathology proved SPTP. In the 23 patients, 21 cases were female (91.3%) and 2 were male (8.7%). The most common symptom was abdominal discomfort with dull pain in 12 patients (52.2%). Others included the pancreatic mass that was detected incidentally during physical examination in 9 patients (39.1%), nausea/vomiting in 2 patients (8.7%). And 1 case of female patients had 2 lesions. In the 24 tumors, 6 cases were located at the head (25.0%), 3 were at neck (12.5%), 8 cases were at body (33.3%), and 7 cases were at tail of pancreas respectively (29.2%). The long-axis diameter ranged from 2.1 cm to 20.1 cm (mean 6.4 cm). 9 tumors were mostly solid component (37.5%), 10 tumors were contained similar proportion of solid and cystic part (41.7%), and mainly cystic components in 5 tumors (20.8%). In 9 of the 23 patients, calcification was found in the tumor (39.1%). In 2 of the 23 patients, bleeding was seen in the mass (8.7%). The dilation of intrahepatic bile duct was found in 1 patient (8.7%). Liver metastasis was showed in one patient (8.7%). On post-contrast CT scan, solid parts demonstrated mild enhancement at the arterial phase. At the portal phase, solid parts were enhanced continuously in all cases, and the enhancement degrees were lower than normal pancreatic tissue. The cystic parts of all lesions showed no enhancement. Pseudo papillary structure, hemorrhage, necrosis, or cystic degeneration were found in all patients by histological study. In a word, SPTP has comparatively characteristic CT imaging features consistent with histological features, when combined with clinical manifestations, could be correctly diagnosed and differentially diagnosed.